1 Troy ounce (used for gold) equals exactly
31,1035 grams
When talking about gold, silver, and other precious metals, the reference unit is not the common (avoirdupois) ounce used for food and everyday items, equal to 28.35 grams, but the Troy ounce, a different and slightly heavier unit, exactly equal to 31.1034768 grams. This distinction is essential for those following the gold financial market: the price of gold quoted 'per ounce' always refers to the Troy ounce.
To convert a measurement from Troy ounces to grams, simply multiply the value in Troy ounces by 31.1035:
To convert from grams to Troy ounces, perform the inverse operation, dividing by 31.1035:
The Troy ounce is used exclusively for precious metals (gold, silver, platinum) in international financial markets. Knowing the difference from the common ounce avoids significant calculation errors for those investing in physical gold, following precious metal quotes, or buying jewelry and bullion, where even a small weight inaccuracy can translate into a considerable difference in value.